We propose a public-private collaborative study to improve the implementation of effective patient safety practices in hospitals. Our Patient Safety Consortium will consist of a partnership between diverse Northern California hospitals, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO), the Institute for Safe Medication Practices (ISMP), the California Healthcare Association (CHA), and the Patient Safety Center of Inquiry (PSCI) at the Department of Veterans' Affairs. The goals of our collaborative research and pilot implementation project are to improve the national evidence base for measuring and predicting potential patient safety problems, and to develop cost-effective strategies for improving patient safety practices at individual hospitals. The project will build on activities related to quality of care and medical errors underway in all of the participating organizations. Our specific aims include: 1. For the vast majority of U.S. hospitals, construct a broad range of potential patient safety indicators (PSIs) that can potentially be used on a routine basis to provide empirical evidence on possible patient safety problems. The PSIs include measures of adverse events, medical errors, and litigation events. 2. Describe recent trends in important patient safety practices at most U.S. hospitals, and use supplemental surveys to describe patient safety practices and "safety cultures" in detail at Consortium hospitals. 3. Examine the empirical relationship between patient safety practices, PSIs, and hospital resource use with statistical methods that recognize the limitations of available measures and potential reporting biases. 4. Conduct an ongoing initiative to help Consortium hospitals share, assess, and improve their patient safety practices, including presentations of our empirical analysis tailored to the individual hospitals. 5. Evaluate the impact of our initiative on Consortium hospitals, by comparing trends in patient safety practices and patient safety performance, as reflected in the PSIs, to a matched control set of nonparticipating hospitals. 6. Prepare manuscripts and present major findings on effective interventions for improving hospital patient safety, and incorporate our findings into the ongoing strategies of the participating organizations to promote patient safety in their member hospitals.